Chroma LoGlow LPF 2″ Mounted Light Pollution Reduction Filter is a broadband photographic filter designed to reduce the influence of artificial lighting on images of the night sky. It selectively suppresses common spectral lines produced by vapour-discharge and metal-halide lamps while maintaining high transmission of useful light from astronomical objects.
Its multiple-band-stop spectral profile preserves a natural colour balance across the visible spectrum. This makes LoGlow well suited to imaging broadband objects such as galaxies, star clusters and reflection nebulae, as well as objects containing prominent emission lines. Transmission of the most important nebular emission lines exceeds 98%.
The filter blocks ultraviolet radiation and infrared wavelengths from 700 to 1100 nm, reducing unwanted signals recorded by sensitive astronomical cameras. Durable magnetron-sputtered coatings are applied to a single optical substrate. The primary filtering coatings are deposited on the front surface, while the rear surface receives an anti-reflection coating that reduces glare and ghost images.
The 1.1 mm thick glass has a blackened edge that reduces internal reflections. A metal cell with a standard 2″ filter thread allows installation in filter wheels, filter drawers and other compatible imaging accessories. The filter is designed for use with telescopes and lenses operating at f/4 or slower.
• broadband light pollution reduction
• selective suppression of common artificial-light emission lines
• natural colour reproduction across the visible spectrum
• transmission of the most important nebular emission lines exceeding 98%
• suitability for imaging galaxies, star clusters and nebulae
• ultraviolet and infrared blocking
• durable magnetron-sputtered coatings
• rear anti-reflection coating reducing glare and ghost images
• blackened glass edge reducing internal reflections
• metal cell with a standard 2″ filter thread
• construction designed for f/4 and slower optical systems
• Chroma LoGlow LPF 2″ filter in a metal cell
• manufacturer: Chroma Technology Corp.
• manufacturer code: CT-27030-2M
• filter type: broadband light pollution reduction filter
• spectral profile: multiple-band-stop filter
• format: 2″, mounted
• cell type: metal with a standard 2″ filter thread
• glass thickness: 1.1 mm
• transmission of the most important nebular lines: above 98%
• infrared blocking: 700–1100 nm
• ultraviolet blocking: yes
• coating technology: durable magnetron-sputtered coatings
• rear-surface coating: anti-reflection
• optical surface accuracy: λ/4 or better
• edge finish: blackened
• recommended optical speed: f/4 or slower
• application: broadband astrophotography
